Multiple-focus lens.



A. J. moss. MULTIPLE FOCUS LENS. APPLIUATION FILED APRJ24, 1914.

1,106,629. Patentet iAug. 11,1914.

WITNESSES -II\IVENTOR Anna-aw JAY oaoss, or NEW YORK, N. Y.

MULTIPLE-FOCUS Specification of Letters Patent.

Patented Aug. llll, W914i;

Application filed April 24, 1914. Serial No. 834,108.

To all whom it may concern:

-Be it known that 1, ANDREW JAY CRoss, a citizen of the United States, residing in the city and county of New York, State of New York, have invented a new and useful inner junction edge of the other member and decentric to the principal axis of said other member. I

It further consists in placing the principal axis of the minor member approximately at the inner junction edge and ap-. proximately at the central vertical meridian and decentric tothe principal axis of the other member.

It further consists of other novel features of construction, all as will be hereinafter fully set forth.

For the purpose of illustrating my invention, I have shown in the-accompanying drawings one form thereof which is at present preferred. by me, since the same will give in practice satisfactory and reliable results, although it is to be understood that the various instrumentalities of which my inventionconsists can be variously arranged and organized and that my invention is not limited tothe precise arrangement and organization of these instrumentalities as herein shown and described.

Figures 1 and 2 represent front elevations of lenses, embodying my invention, showing different forms which may be employed. Fig. 3 represents a vertical sectional view on line w-w of Fig. 2. Figs. 4, 5 and 6 represent elevations showing the lenses employed before being cut, and with the relative location of the principal axis and of the junction edges indicated. Fig. 7 represents a front elevation of a lens embodying my invention, showing another form which may be employed.

In ll multiple focal lenses for spectacles and eye glasses, in which the minor lens member does not have its inner edge, -or line demarking the union between the different focal powers, cut horizontally across. its

principal axis, the change in vision from one focal area to another in the vertical meridian is accompanied by apparent duplica tion of the object looked at, just as the sight crosses this edge, or line, separating the two focal powers or areas. In all multiple focal lenses that do have the visual edge of the minor lens member cut on the principal focal axis, these minor lens members are located with the principal axis coincident with the geometric center of the major lens, or coincident with the principal axis of the major lens when geometrically decentered.

In other cases, the minor lenses have not been cut on their principal axes, nor have their principal axes been located coincident with the geometric center of the major lens. In the present a plication, I have provided a construction 0 a multiple focus lens having a plurality of focal powers and composed of members, the principal axis of one of the members being located approximately at the junction edge with the other member and decentric to the principal axis of said member whereby, substantially at the central verticalmeridian, doubling of the image is prevented in passing from one focal power to the other, and where the edge of the minor lens is formed straight, there will be no doubling of the image in any vertical meridian, but in the construction where the minor lens is made with a curved edge, there may be slight doubling of the image, if the eye passes from one focal power to the other, at a point laterally removed from the.

said central vertical meridian, but asthe eye, in nearly all instances, in making the vertical excursion, will pass from one focal power to. the other, substantially at the central vertical meridian, the doubling of images is overcome at this vertical meridian in that corresponding parts in the figures.

Referring to the drawings :-1 designates what I term the major lens, and a portion of which serves as the readin lens or as the close vision portion. 2 deslgnates a second lens, which may be termed one of the minor lenses, and which,in the present embodiment,

imposed upon the lens 1 in order that a suit-- able portion of said minor lens 2, when combined with a portion of the major lens 1,

1 will produce a portion of different focal power, and which may be termed the interv mediate vision portion. 3 designates a third lens or member, which may be considered as a second minor lens and which, the present embodiment, is shown as a lens with a portion or segment thereof removed, and which tapers from the upper portion thereof downwardly to a thin edge and which minor lens 3 is, as here shown, superposed upon the i up er ortion of the other minor lens 2, in

- or er t at the combination or combined ef feet of the said minor lens 3, the portion of the said minor lens 2, and a portion of the -major lens 1, when combined, will produce a vision portion of different focal strength and which, as here shown, will serve as the distance vision portion.

In carrying out my invention, the principal axis of the major lens may be located approximately at the geometrical center thereof, or at some other location not coincident with the principal axis of a minor member, while the principal axis of the minor lens 2 is formed substantially or approximately at the inner junction edge of the same with the major lens 1, and the principal axis of the minor lens 3, which is located approximately or substantially at the inner junction edge thereof with the minor lens 2, and I preferably desire to locate the principal axes of the two minor lenses substantially or approximately at the central vertical meridian. In the drawings, I have indicated the rincipal axis of the major lens substantially at a point, as 4, the principal axis of the minor lens 2 at a point approximately at 5, and the principal axis of light, and it is moreover a' simple matter to the minor lens 3 approximately at a point 6. By this means, it willbe understood that I disclose means to prevent visual -.dedoublements, and I produce a multiple focal lens which ermits the vision to pass up or down along t e vertical meridian without causin any doubling of the objects, or so-calle jump resembling rismatic displacements, at any point on t of the complete lens.

I have, as previously stated, combined the lens members to have theiredges placed at a desired distance apart, independent of the principal focal axis and of the geometric center of the major lens member and have thus provided a multiple focal lenswhich is successful in operation and. which is easy of combination, since it will be understood that the members may be round in such a manner'that the lens can e kept quite thin and e vertical meridian vised a novel and useful multiple focuslens,

which embodies the features of advantage enumerated as desirable in the statement of the mvention and the above description,

and while I have, in the present instance, .shown and described apreferred embodiment thereof which 'will give inpractice, satisfactory and reliable results, it isto be understood that the same is susceptible of modification in various particulars without departing from the spirit or scope of the invention or sacrificing any of its advantages.

Having thus described my invention, what I claim'as new and desire to secure by Letters Patent, is':-

1. A multiple focus lens composed of major and minor lens members, the minor member having its principal axis located approximately at the inner edge and approximately at its central vertical meridian, and the minor member having its principal axis decentric to the principal axis of the major member. I

2. A multiple focus lens composed of maj or and minor lens members, the minor member having its principal axis located ap proximately att e inner edge and approximately at its central vertical meridian, and the minor member having its principal axis vertically decentric to the principal axis of the major member.

'3. A multiple focus lens having a plurality of focal powers, composed of members, the principal axis of one of said members being located approximately at the junction edge withthe other .member and decentric to the principal axis of said other member.

4. .A lens formed with a distance vision portion, an intermediate vision portion and a close vision portion, the princlpal axes of two of the portions bein respectively located a proximately at t e junction: edges of the dlflerent vision portions."

5. A lens formed with a' distance vision portion, an intermediate vision portion and a close .vis1on portion, the principal axes of two of theportions bein respectively located approximately at t e junction edges of the difi'er'ent vision portions and approximatelX at the central vertical meridian.

6. lens'formed with a distance vision portion, an intermediatevision portionand a close vision portion, the principal axes of two of the portions being respectively located approximatel at the junction edges of the ifit'erent visloii portions, and decenlocated, and the minor member having its trio to the principal axis of the other portion. 7 I

7. A lens formedwith adistance visionportion, an intermediate vision portion and a close vision portion, the principal axes of two of the portions being respectively located approximately at the junction edges of the difierent vision portions, approximately at the central vertical meridian, and decentric to the principal axis of the other portion.

8. A multiple focus lens composed of three lens members, two of said members being incomplet'eand'so mounted'upon the third member as to provide a distance vision portion, an intermediate vision portion and a close vision portion, the principal axes of the said incomplete members being located at approximately the inner junction edges thereof. 1

.9; A multiple focus lens composed of a major and two minor lenses, said. lenses being suitably located with respect to each other with the principal axes of the minor lenses located approximately at their inner junction edges and decentric'to the principal axis of the major lens.

10. A multiple focus lens, composed of major and minor lens members, the ma'or member having its principal axis suitably inner line of junction cut approximate at the point of location of its principal axis and having said line of junction located ldecentric to the principal axis of said major member. s

11. A trifocal lens, formed of one complete or major member and two incomplete 'or minor members, the major member forming the near-vision portion, the larger of the incomplete members overhanging the said major member and forming therewith the intermediate vision portion, and the smaller of the said minor members overhanging the said other two members and forming with them the distance vision portion, the principal axes of saidtwo minor members being located approximately at their inner junction edges.

12. A multiple focus lens having a plurality of focal powers, composed of major and minor members, the principal axis of said minor member being located approximately at the thinnest portion thereof, and approximately decentric with respect to the principal axis of the major member, when combined.

' 1 3. A-multiple focus lens, composed of ma or and minorlens members, the major member having its principal axis suitably located, the minor lens member having its inner line of junction cut horizontally and approximately at the point of location of its principal axis and having said line of junction decentric to the prlnclpal axis of said major lens.

14. A multiple focus lens, comprising a major and minor lens member, the major member having its principal axis suitably located, and the minor member having its inner line of junction formed with a'curved edge and cut approximately at a given vertical'meridian at the point of location of its principalaxis and having said line of junction located decentric to the prmcipal axis of said major member.

" ANDREW JAY CROSS. Witnesses:

THOMAS SPRoULL,

' 'MABEL M. GLASSEY. 

